1. Technical Field
The present invention relates generally to a composition that can be used for cleaning and disinfecting a hard surface in one step with a relatively short contact time. More particularly, it relates to a composition that will clean and disinfect a surface by killing 99.999% of bacteria in under five minutes. This is accomplished while still keeping the amount of expensive ingredients such as quaternary ammonium compounds and polymeric biguanide, each contained in the composition at low levels of at least 5 ppm in a diluted form or when diluted from a concentrated form.
2. Background Art
The cleaning and disinfecting of hard surfaces is important in both residential and commercial settings. The increasing importance of hygiene combined with the fast moving pace of the modem world has created a need for products with fast cleaning and disinfecting action. The main concerns are to effectively reduce bacteria in the short span of time the product is permitted to contact the surface while still maintaining a reasonable cost for the product allowing it to be feasible for commercial use. The use of a cleaner disinfectant concentrate in a liquid form is beneficial in that cleaning a surface and additionally elimination of bacteria is achieved in one step. The one step process reduces the bacteria that could cause contamination of other items placed on the surface such as food.
The European Union standard suspension test, European Norm 1276 (EN1276), is a standard test for evaluation of the effectiveness of biocides in the European Union. The test was designed to simulate dirty conditions allowing for the evaluation of results of a product, experienced with simultaneously cleaning and disinfecting. Organic soils and hard water are known to interfere with the activity of biocides, so the use of "interfering substances" namely, bovine albumin (0.3%) and hard water (300 ppm), represent the soil likely to be found when cleaning. The use of these interfering substances in the presence of quantitatively and qualitatively known bacteria (pseudomonas aeruginosa, the most difficult bacteria to kill; esherichia coli; staphylococcus aureus; enteroccus hire; amongst others) ensures a rigorous test standard ("dirty conditions"). To pass EN1276 and to claim a disinfectant product, a log 5 reduction (99.999% kill) of the bacteria must be attained at 20.degree. C.
The use of Cleaner Disinfectant Concentrates is widespread throughout the industry, the majority being based on quaternary ammonium compounds. However, the kill of 99.999% of bacteria is normally met with long contact times (5 minutes or more) and by the use of products that contain very high levels of biocidal actives (much more than 300 ppm each). The consequence of using either a quaternary ammonium chloride or a polymeric biguanide alone is that they must be used in higher quantities to even achieve a satisfactory result at a time over five minutes. Additionally, the use of higher quantities results in a higher cost that is not commercially feasible. Polymeric biguanide is a particularly expensive biocide. The use of combinations of biocides until now has been ineffective in reducing the time necessary to eliminate 99.999% of the bacteria in the EN1276 test. The kill times have remained 5 minutes, which is excessive for the elimination of bacteria in a commercial setting or domestic setting because normal contact time of a cleaning an disinfecting composition within the work place or home is under five minutes.
U.S. Pat. No. 5,529,713 claims a cleaning and disinfectant solution that contains quaternary ammonium chlorides and biguanide hydrochloride. This patent teaches the use of two or more quaternary ammonium chlorides and biguanide hydrochloride. The patent also teaches the use of two different quaternary ammonium salts in combination and a biguanide hydrochloride in order to have an effective bacterial reduction after five minutes which is unacceptable in the settings the product will be used. This patent further teaches the use of isopropyl alcohol, which very volatile evaporating quickly and also extremely flammable. The patent lastly does not teach the use of a sequestrant in combination with the quaternary ammonium chlorides and the biguanide hydrochloride.
PCT patent publication WO 98/47359 describes a biocide composition without cleaning capabilities. The patent teaches the use of one quaternary ammonium chloride in over one percent and an amount of biguanide or another quaternary ammonium three percent or over in order to reduce bacteria in over five minutes. The patent also teaches the use of a high level of the biguanide or quaternary ammonium chloride is used without a sequestrant, in order to reduce a broad spectrum of bacteria that may be present.
Sales information distributed by Zeneca Biocides, 1800 Concord Pike Wilmington, Del. 19850, suggests the combination of quaternary ammonium salts and a polymeric biguanide compound at a high percentage and at a ratio of 2:1 in order to have broad range bacterial reduction. The information is presented in relation to their product "Vantocil" that is a biguanide solution.